Because we now live in an astonishing time of endless possibility. We cannot conquer the mountains, but our railroads now run through them with ease... We cannot defeat the river, but we can dam it and divert it for our own purposes. The oceans are too vast to contemplate, but our seawalls can blunt their fury and our steamships can defy the wind and currents to navigate upon them. In our scalpel work, we too, are pushing back with great success. More has been learned about the treatment of the human body in the last five years than has been learned in the previous five-hundred. Twenty years ago, thirty-nine was the number of years a man could expect from his life, today it is more than forty-seven!... Eventually, the train tunnels will crumble, the dams will be overrun, the ships sank, the seawalls eroded, and our patients’ hearts will all cease their beating... Nature will never lose the war, but we humans can get in a few good licks in battle before we surrender.